Many times during the laboratory and flight testing of flight management systems (e.g., autopilot, autothrottle and flight management computer systems) momentary monitor display anomalies appear. Unfortunately, the engineers and pilots who observe such anomalies often cannot satisfactorily describe them in a manner that enables their resolution. Further, the normal recording instrumentation creates a huge mass of data that must be shifted through and organized in order to diagnose aircraft avionics problems, including monitor display anomalies, after they occur.
Pilots of aircraft in service have the same problem. That is, they occasionally observe momentary monitor display anomalies, i.e., they observe anomalies in display monitors associated with flight management systems. Often the reports of such FMS display monitor anomalies lack clarity and, thus, cannot be properly diagnosed. As a result, engineering time is wasted trying to solve monitor anomaly problems, regardless of whether they originate in a laboratory environment, a flight test environment or an inservice environment.
Modern "glass" flight decks, which rely on a few page display monitors to display a variety of information, have greatly enhanced the problems associated with momentary monitor display anomalies. The diagnosis difficulty is further enhanced by the fact that modern aircraft produce more data than present day flight recorders are capable of storing for an extended period of time. As a result, a substantial amount of desirable data is either not recorded or rapidly lost. For example, control display unit (CDU) key pushes are important when analyzing a monitor display anomaly because erroneous pushes can create the source of the anomaly. A time history of key pushes is also a desirable piece of information to have available when diagnosing momentary monitor display anomalies. A record of the time history of page displays is also desirable, as is navigational and other information, depending upon the nature of the avionic system or systems being monitored.
While various types of avionic monitors have been developed, none has satisfactorily addressed the problems associated with momentary monitor display anomalies. A CDU monitor built for use with the 737-300 aircraft produced by the Boeing Company uses reformatted lateral guidance and buffer dumps in the same program to provide diagnostic information regarding the state of internal variables as well as navigational display anomalies. Unfortunately, this monitor fails to provide diagnostics with respect to the general state of the variables of an integrated flight management system. This monitor also fails to provide diagnostics in an expeditious manner since it requires that data be processed prior to being analyzed.
The present invention is directed to a general purpose avionics display monitor that overcomes the disadvantages of prior monitoring systems. More specifically, the present invention is directed to a general purpose avionics display monitor that is ideally suited for viewing, recording and storing information about flight management system anomalies, particularly momentary monitor display anomalies so that such anomalies can be readily evaluated when they occur or at a later date. The invention is particularly usable with modern "glass" flight decks that include one or more multipurpose control display units (MCDUs).